As a functional modeling technique to represent design information including designer's intention, the Multilevel Flow Modelling (MFM) proposed by Lind has been investigated. The MFM has the problems that (1) it can not model the change of energy form and (2) it has little relation to what is called design chart because it does not represent system structure. The problem of item (1) is solved by expressing explicitly the energy form such as heat, and so on. To get rid of the problem of item (2), the strucuture-function and structure models are added to a MFM model. A four layrs design model composed of goal, function-goal, function-structure, and structure models are proposed.An interface system is developed to make four layrs design models on a Smalltalk-80. The design information of a central heating system and a dust process system is expressed using the interface system. Through the expression trials, design information is confirmed to be expressed systematically and in well organized form. Moreover, it is shown that the difference of design intention is clearly expressed. A simple support system to assign structure to functions is also developed.The system behavior is derived from the system structure expressed in the four layrs design model by applying the Hybrid Phenomena (HPT) proposed by Woods and combining system structure model and numerical simulation programs. The HPT is extended to treat multiple models by introducing the factors of modeling ontologies proposed by Kiriyama. The effectiveness of the techniques of structure assignment to functions and behavior derivation is examined by a conceptual design of the central heating system.